Linux 4.16.11
[linux/fpc-iii.git] / drivers / target / target_core_sbc.c
blobb054682e974f91c05fa4c640e314e69397646a93
1 /*
2 * SCSI Block Commands (SBC) parsing and emulation.
4 * (c) Copyright 2002-2013 Datera, Inc.
6 * Nicholas A. Bellinger <nab@kernel.org>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/ratelimit.h>
26 #include <linux/crc-t10dif.h>
27 #include <linux/t10-pi.h>
28 #include <asm/unaligned.h>
29 #include <scsi/scsi_proto.h>
30 #include <scsi/scsi_tcq.h>
32 #include <target/target_core_base.h>
33 #include <target/target_core_backend.h>
34 #include <target/target_core_fabric.h>
36 #include "target_core_internal.h"
37 #include "target_core_ua.h"
38 #include "target_core_alua.h"
40 static sense_reason_t
41 sbc_check_prot(struct se_device *, struct se_cmd *, unsigned char *, u32, bool);
42 static sense_reason_t sbc_execute_unmap(struct se_cmd *cmd);
44 static sense_reason_t
45 sbc_emulate_readcapacity(struct se_cmd *cmd)
47 struct se_device *dev = cmd->se_dev;
48 unsigned char *cdb = cmd->t_task_cdb;
49 unsigned long long blocks_long = dev->transport->get_blocks(dev);
50 unsigned char *rbuf;
51 unsigned char buf[8];
52 u32 blocks;
55 * SBC-2 says:
56 * If the PMI bit is set to zero and the LOGICAL BLOCK
57 * ADDRESS field is not set to zero, the device server shall
58 * terminate the command with CHECK CONDITION status with
59 * the sense key set to ILLEGAL REQUEST and the additional
60 * sense code set to INVALID FIELD IN CDB.
62 * In SBC-3, these fields are obsolete, but some SCSI
63 * compliance tests actually check this, so we might as well
64 * follow SBC-2.
66 if (!(cdb[8] & 1) && !!(cdb[2] | cdb[3] | cdb[4] | cdb[5]))
67 return TCM_INVALID_CDB_FIELD;
69 if (blocks_long >= 0x00000000ffffffff)
70 blocks = 0xffffffff;
71 else
72 blocks = (u32)blocks_long;
74 put_unaligned_be32(blocks, &buf[0]);
75 put_unaligned_be32(dev->dev_attrib.block_size, &buf[4]);
77 rbuf = transport_kmap_data_sg(cmd);
78 if (rbuf) {
79 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
80 transport_kunmap_data_sg(cmd);
83 target_complete_cmd_with_length(cmd, GOOD, 8);
84 return 0;
87 static sense_reason_t
88 sbc_emulate_readcapacity_16(struct se_cmd *cmd)
90 struct se_device *dev = cmd->se_dev;
91 struct se_session *sess = cmd->se_sess;
92 int pi_prot_type = dev->dev_attrib.pi_prot_type;
94 unsigned char *rbuf;
95 unsigned char buf[32];
96 unsigned long long blocks = dev->transport->get_blocks(dev);
98 memset(buf, 0, sizeof(buf));
99 put_unaligned_be64(blocks, &buf[0]);
100 put_unaligned_be32(dev->dev_attrib.block_size, &buf[8]);
102 * Set P_TYPE and PROT_EN bits for DIF support
104 if (sess->sup_prot_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS)) {
106 * Only override a device's pi_prot_type if no T10-PI is
107 * available, and sess_prot_type has been explicitly enabled.
109 if (!pi_prot_type)
110 pi_prot_type = sess->sess_prot_type;
112 if (pi_prot_type)
113 buf[12] = (pi_prot_type - 1) << 1 | 0x1;
116 if (dev->transport->get_lbppbe)
117 buf[13] = dev->transport->get_lbppbe(dev) & 0x0f;
119 if (dev->transport->get_alignment_offset_lbas) {
120 u16 lalba = dev->transport->get_alignment_offset_lbas(dev);
122 put_unaligned_be16(lalba, &buf[14]);
126 * Set Thin Provisioning Enable bit following sbc3r22 in section
127 * READ CAPACITY (16) byte 14 if emulate_tpu or emulate_tpws is enabled.
129 if (dev->dev_attrib.emulate_tpu || dev->dev_attrib.emulate_tpws) {
130 buf[14] |= 0x80;
133 * LBPRZ signifies that zeroes will be read back from an LBA after
134 * an UNMAP or WRITE SAME w/ unmap bit (sbc3r36 5.16.2)
136 if (dev->dev_attrib.unmap_zeroes_data)
137 buf[14] |= 0x40;
140 rbuf = transport_kmap_data_sg(cmd);
141 if (rbuf) {
142 memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
143 transport_kunmap_data_sg(cmd);
146 target_complete_cmd_with_length(cmd, GOOD, 32);
147 return 0;
150 static sense_reason_t
151 sbc_emulate_startstop(struct se_cmd *cmd)
153 unsigned char *cdb = cmd->t_task_cdb;
156 * See sbc3r36 section 5.25
157 * Immediate bit should be set since there is nothing to complete
158 * POWER CONDITION MODIFIER 0h
160 if (!(cdb[1] & 1) || cdb[2] || cdb[3])
161 return TCM_INVALID_CDB_FIELD;
164 * See sbc3r36 section 5.25
165 * POWER CONDITION 0h START_VALID - process START and LOEJ
167 if (cdb[4] >> 4 & 0xf)
168 return TCM_INVALID_CDB_FIELD;
171 * See sbc3r36 section 5.25
172 * LOEJ 0h - nothing to load or unload
173 * START 1h - we are ready
175 if (!(cdb[4] & 1) || (cdb[4] & 2) || (cdb[4] & 4))
176 return TCM_INVALID_CDB_FIELD;
178 target_complete_cmd(cmd, SAM_STAT_GOOD);
179 return 0;
182 sector_t sbc_get_write_same_sectors(struct se_cmd *cmd)
184 u32 num_blocks;
186 if (cmd->t_task_cdb[0] == WRITE_SAME)
187 num_blocks = get_unaligned_be16(&cmd->t_task_cdb[7]);
188 else if (cmd->t_task_cdb[0] == WRITE_SAME_16)
189 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[10]);
190 else /* WRITE_SAME_32 via VARIABLE_LENGTH_CMD */
191 num_blocks = get_unaligned_be32(&cmd->t_task_cdb[28]);
194 * Use the explicit range when non zero is supplied, otherwise calculate
195 * the remaining range based on ->get_blocks() - starting LBA.
197 if (num_blocks)
198 return num_blocks;
200 return cmd->se_dev->transport->get_blocks(cmd->se_dev) -
201 cmd->t_task_lba + 1;
203 EXPORT_SYMBOL(sbc_get_write_same_sectors);
205 static sense_reason_t
206 sbc_execute_write_same_unmap(struct se_cmd *cmd)
208 struct sbc_ops *ops = cmd->protocol_data;
209 sector_t nolb = sbc_get_write_same_sectors(cmd);
210 sense_reason_t ret;
212 if (nolb) {
213 ret = ops->execute_unmap(cmd, cmd->t_task_lba, nolb);
214 if (ret)
215 return ret;
218 target_complete_cmd(cmd, GOOD);
219 return 0;
222 static sense_reason_t
223 sbc_emulate_noop(struct se_cmd *cmd)
225 target_complete_cmd(cmd, GOOD);
226 return 0;
229 static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
231 return cmd->se_dev->dev_attrib.block_size * sectors;
234 static inline u32 transport_get_sectors_6(unsigned char *cdb)
237 * Use 8-bit sector value. SBC-3 says:
239 * A TRANSFER LENGTH field set to zero specifies that 256
240 * logical blocks shall be written. Any other value
241 * specifies the number of logical blocks that shall be
242 * written.
244 return cdb[4] ? : 256;
247 static inline u32 transport_get_sectors_10(unsigned char *cdb)
249 return get_unaligned_be16(&cdb[7]);
252 static inline u32 transport_get_sectors_12(unsigned char *cdb)
254 return get_unaligned_be32(&cdb[6]);
257 static inline u32 transport_get_sectors_16(unsigned char *cdb)
259 return get_unaligned_be32(&cdb[10]);
263 * Used for VARIABLE_LENGTH_CDB WRITE_32 and READ_32 variants
265 static inline u32 transport_get_sectors_32(unsigned char *cdb)
267 return get_unaligned_be32(&cdb[28]);
271 static inline u32 transport_lba_21(unsigned char *cdb)
273 return get_unaligned_be24(&cdb[1]) & 0x1fffff;
276 static inline u32 transport_lba_32(unsigned char *cdb)
278 return get_unaligned_be32(&cdb[2]);
281 static inline unsigned long long transport_lba_64(unsigned char *cdb)
283 return get_unaligned_be64(&cdb[2]);
287 * For VARIABLE_LENGTH_CDB w/ 32 byte extended CDBs
289 static inline unsigned long long transport_lba_64_ext(unsigned char *cdb)
291 return get_unaligned_be64(&cdb[12]);
294 static sense_reason_t
295 sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
297 struct se_device *dev = cmd->se_dev;
298 sector_t end_lba = dev->transport->get_blocks(dev) + 1;
299 unsigned int sectors = sbc_get_write_same_sectors(cmd);
300 sense_reason_t ret;
302 if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
303 pr_err("WRITE_SAME PBDATA and LBDATA"
304 " bits not supported for Block Discard"
305 " Emulation\n");
306 return TCM_UNSUPPORTED_SCSI_OPCODE;
308 if (sectors > cmd->se_dev->dev_attrib.max_write_same_len) {
309 pr_warn("WRITE_SAME sectors: %u exceeds max_write_same_len: %u\n",
310 sectors, cmd->se_dev->dev_attrib.max_write_same_len);
311 return TCM_INVALID_CDB_FIELD;
314 * Sanity check for LBA wrap and request past end of device.
316 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
317 ((cmd->t_task_lba + sectors) > end_lba)) {
318 pr_err("WRITE_SAME exceeds last lba %llu (lba %llu, sectors %u)\n",
319 (unsigned long long)end_lba, cmd->t_task_lba, sectors);
320 return TCM_ADDRESS_OUT_OF_RANGE;
323 /* We always have ANC_SUP == 0 so setting ANCHOR is always an error */
324 if (flags[0] & 0x10) {
325 pr_warn("WRITE SAME with ANCHOR not supported\n");
326 return TCM_INVALID_CDB_FIELD;
329 * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
330 * translated into block discard requests within backend code.
332 if (flags[0] & 0x08) {
333 if (!ops->execute_unmap)
334 return TCM_UNSUPPORTED_SCSI_OPCODE;
336 if (!dev->dev_attrib.emulate_tpws) {
337 pr_err("Got WRITE_SAME w/ UNMAP=1, but backend device"
338 " has emulate_tpws disabled\n");
339 return TCM_UNSUPPORTED_SCSI_OPCODE;
341 cmd->execute_cmd = sbc_execute_write_same_unmap;
342 return 0;
344 if (!ops->execute_write_same)
345 return TCM_UNSUPPORTED_SCSI_OPCODE;
347 ret = sbc_check_prot(dev, cmd, &cmd->t_task_cdb[0], sectors, true);
348 if (ret)
349 return ret;
351 cmd->execute_cmd = ops->execute_write_same;
352 return 0;
355 static sense_reason_t xdreadwrite_callback(struct se_cmd *cmd, bool success,
356 int *post_ret)
358 unsigned char *buf, *addr;
359 struct scatterlist *sg;
360 unsigned int offset;
361 sense_reason_t ret = TCM_NO_SENSE;
362 int i, count;
364 * From sbc3r22.pdf section 5.48 XDWRITEREAD (10) command
366 * 1) read the specified logical block(s);
367 * 2) transfer logical blocks from the data-out buffer;
368 * 3) XOR the logical blocks transferred from the data-out buffer with
369 * the logical blocks read, storing the resulting XOR data in a buffer;
370 * 4) if the DISABLE WRITE bit is set to zero, then write the logical
371 * blocks transferred from the data-out buffer; and
372 * 5) transfer the resulting XOR data to the data-in buffer.
374 buf = kmalloc(cmd->data_length, GFP_KERNEL);
375 if (!buf) {
376 pr_err("Unable to allocate xor_callback buf\n");
377 return TCM_OUT_OF_RESOURCES;
380 * Copy the scatterlist WRITE buffer located at cmd->t_data_sg
381 * into the locally allocated *buf
383 sg_copy_to_buffer(cmd->t_data_sg,
384 cmd->t_data_nents,
385 buf,
386 cmd->data_length);
389 * Now perform the XOR against the BIDI read memory located at
390 * cmd->t_mem_bidi_list
393 offset = 0;
394 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, count) {
395 addr = kmap_atomic(sg_page(sg));
396 if (!addr) {
397 ret = TCM_OUT_OF_RESOURCES;
398 goto out;
401 for (i = 0; i < sg->length; i++)
402 *(addr + sg->offset + i) ^= *(buf + offset + i);
404 offset += sg->length;
405 kunmap_atomic(addr);
408 out:
409 kfree(buf);
410 return ret;
413 static sense_reason_t
414 sbc_execute_rw(struct se_cmd *cmd)
416 struct sbc_ops *ops = cmd->protocol_data;
418 return ops->execute_rw(cmd, cmd->t_data_sg, cmd->t_data_nents,
419 cmd->data_direction);
422 static sense_reason_t compare_and_write_post(struct se_cmd *cmd, bool success,
423 int *post_ret)
425 struct se_device *dev = cmd->se_dev;
426 sense_reason_t ret = TCM_NO_SENSE;
429 * Only set SCF_COMPARE_AND_WRITE_POST to force a response fall-through
430 * within target_complete_ok_work() if the command was successfully
431 * sent to the backend driver.
433 spin_lock_irq(&cmd->t_state_lock);
434 if (cmd->transport_state & CMD_T_SENT) {
435 cmd->se_cmd_flags |= SCF_COMPARE_AND_WRITE_POST;
436 *post_ret = 1;
438 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
439 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
441 spin_unlock_irq(&cmd->t_state_lock);
444 * Unlock ->caw_sem originally obtained during sbc_compare_and_write()
445 * before the original READ I/O submission.
447 up(&dev->caw_sem);
449 return ret;
452 static sense_reason_t compare_and_write_callback(struct se_cmd *cmd, bool success,
453 int *post_ret)
455 struct se_device *dev = cmd->se_dev;
456 struct scatterlist *write_sg = NULL, *sg;
457 unsigned char *buf = NULL, *addr;
458 struct sg_mapping_iter m;
459 unsigned int offset = 0, len;
460 unsigned int nlbas = cmd->t_task_nolb;
461 unsigned int block_size = dev->dev_attrib.block_size;
462 unsigned int compare_len = (nlbas * block_size);
463 sense_reason_t ret = TCM_NO_SENSE;
464 int rc, i;
467 * Handle early failure in transport_generic_request_failure(),
468 * which will not have taken ->caw_sem yet..
470 if (!success && (!cmd->t_data_sg || !cmd->t_bidi_data_sg))
471 return TCM_NO_SENSE;
473 * Handle special case for zero-length COMPARE_AND_WRITE
475 if (!cmd->data_length)
476 goto out;
478 * Immediately exit + release dev->caw_sem if command has already
479 * been failed with a non-zero SCSI status.
481 if (cmd->scsi_status) {
482 pr_debug("compare_and_write_callback: non zero scsi_status:"
483 " 0x%02x\n", cmd->scsi_status);
484 *post_ret = 1;
485 if (cmd->scsi_status == SAM_STAT_CHECK_CONDITION)
486 ret = TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
487 goto out;
490 buf = kzalloc(cmd->data_length, GFP_KERNEL);
491 if (!buf) {
492 pr_err("Unable to allocate compare_and_write buf\n");
493 ret = TCM_OUT_OF_RESOURCES;
494 goto out;
497 write_sg = kmalloc_array(cmd->t_data_nents, sizeof(*write_sg),
498 GFP_KERNEL);
499 if (!write_sg) {
500 pr_err("Unable to allocate compare_and_write sg\n");
501 ret = TCM_OUT_OF_RESOURCES;
502 goto out;
504 sg_init_table(write_sg, cmd->t_data_nents);
506 * Setup verify and write data payloads from total NumberLBAs.
508 rc = sg_copy_to_buffer(cmd->t_data_sg, cmd->t_data_nents, buf,
509 cmd->data_length);
510 if (!rc) {
511 pr_err("sg_copy_to_buffer() failed for compare_and_write\n");
512 ret = TCM_OUT_OF_RESOURCES;
513 goto out;
516 * Compare against SCSI READ payload against verify payload
518 for_each_sg(cmd->t_bidi_data_sg, sg, cmd->t_bidi_data_nents, i) {
519 addr = (unsigned char *)kmap_atomic(sg_page(sg));
520 if (!addr) {
521 ret = TCM_OUT_OF_RESOURCES;
522 goto out;
525 len = min(sg->length, compare_len);
527 if (memcmp(addr, buf + offset, len)) {
528 pr_warn("Detected MISCOMPARE for addr: %p buf: %p\n",
529 addr, buf + offset);
530 kunmap_atomic(addr);
531 goto miscompare;
533 kunmap_atomic(addr);
535 offset += len;
536 compare_len -= len;
537 if (!compare_len)
538 break;
541 i = 0;
542 len = cmd->t_task_nolb * block_size;
543 sg_miter_start(&m, cmd->t_data_sg, cmd->t_data_nents, SG_MITER_TO_SG);
545 * Currently assumes NoLB=1 and SGLs are PAGE_SIZE..
547 while (len) {
548 sg_miter_next(&m);
550 if (block_size < PAGE_SIZE) {
551 sg_set_page(&write_sg[i], m.page, block_size,
552 m.piter.sg->offset + block_size);
553 } else {
554 sg_miter_next(&m);
555 sg_set_page(&write_sg[i], m.page, block_size,
556 m.piter.sg->offset);
558 len -= block_size;
559 i++;
561 sg_miter_stop(&m);
563 * Save the original SGL + nents values before updating to new
564 * assignments, to be released in transport_free_pages() ->
565 * transport_reset_sgl_orig()
567 cmd->t_data_sg_orig = cmd->t_data_sg;
568 cmd->t_data_sg = write_sg;
569 cmd->t_data_nents_orig = cmd->t_data_nents;
570 cmd->t_data_nents = 1;
572 cmd->sam_task_attr = TCM_HEAD_TAG;
573 cmd->transport_complete_callback = compare_and_write_post;
575 * Now reset ->execute_cmd() to the normal sbc_execute_rw() handler
576 * for submitting the adjusted SGL to write instance user-data.
578 cmd->execute_cmd = sbc_execute_rw;
580 spin_lock_irq(&cmd->t_state_lock);
581 cmd->t_state = TRANSPORT_PROCESSING;
582 cmd->transport_state |= CMD_T_ACTIVE | CMD_T_SENT;
583 spin_unlock_irq(&cmd->t_state_lock);
585 __target_execute_cmd(cmd, false);
587 kfree(buf);
588 return ret;
590 miscompare:
591 pr_warn("Target/%s: Send MISCOMPARE check condition and sense\n",
592 dev->transport->name);
593 ret = TCM_MISCOMPARE_VERIFY;
594 out:
596 * In the MISCOMPARE or failure case, unlock ->caw_sem obtained in
597 * sbc_compare_and_write() before the original READ I/O submission.
599 up(&dev->caw_sem);
600 kfree(write_sg);
601 kfree(buf);
602 return ret;
605 static sense_reason_t
606 sbc_compare_and_write(struct se_cmd *cmd)
608 struct sbc_ops *ops = cmd->protocol_data;
609 struct se_device *dev = cmd->se_dev;
610 sense_reason_t ret;
611 int rc;
613 * Submit the READ first for COMPARE_AND_WRITE to perform the
614 * comparision using SGLs at cmd->t_bidi_data_sg..
616 rc = down_interruptible(&dev->caw_sem);
617 if (rc != 0) {
618 cmd->transport_complete_callback = NULL;
619 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
622 * Reset cmd->data_length to individual block_size in order to not
623 * confuse backend drivers that depend on this value matching the
624 * size of the I/O being submitted.
626 cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size;
628 ret = ops->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents,
629 DMA_FROM_DEVICE);
630 if (ret) {
631 cmd->transport_complete_callback = NULL;
632 up(&dev->caw_sem);
633 return ret;
636 * Unlock of dev->caw_sem to occur in compare_and_write_callback()
637 * upon MISCOMPARE, or in compare_and_write_done() upon completion
638 * of WRITE instance user-data.
640 return TCM_NO_SENSE;
643 static int
644 sbc_set_prot_op_checks(u8 protect, bool fabric_prot, enum target_prot_type prot_type,
645 bool is_write, struct se_cmd *cmd)
647 if (is_write) {
648 cmd->prot_op = fabric_prot ? TARGET_PROT_DOUT_STRIP :
649 protect ? TARGET_PROT_DOUT_PASS :
650 TARGET_PROT_DOUT_INSERT;
651 switch (protect) {
652 case 0x0:
653 case 0x3:
654 cmd->prot_checks = 0;
655 break;
656 case 0x1:
657 case 0x5:
658 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
659 if (prot_type == TARGET_DIF_TYPE1_PROT)
660 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
661 break;
662 case 0x2:
663 if (prot_type == TARGET_DIF_TYPE1_PROT)
664 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
665 break;
666 case 0x4:
667 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
668 break;
669 default:
670 pr_err("Unsupported protect field %d\n", protect);
671 return -EINVAL;
673 } else {
674 cmd->prot_op = fabric_prot ? TARGET_PROT_DIN_INSERT :
675 protect ? TARGET_PROT_DIN_PASS :
676 TARGET_PROT_DIN_STRIP;
677 switch (protect) {
678 case 0x0:
679 case 0x1:
680 case 0x5:
681 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
682 if (prot_type == TARGET_DIF_TYPE1_PROT)
683 cmd->prot_checks |= TARGET_DIF_CHECK_REFTAG;
684 break;
685 case 0x2:
686 if (prot_type == TARGET_DIF_TYPE1_PROT)
687 cmd->prot_checks = TARGET_DIF_CHECK_REFTAG;
688 break;
689 case 0x3:
690 cmd->prot_checks = 0;
691 break;
692 case 0x4:
693 cmd->prot_checks = TARGET_DIF_CHECK_GUARD;
694 break;
695 default:
696 pr_err("Unsupported protect field %d\n", protect);
697 return -EINVAL;
701 return 0;
704 static sense_reason_t
705 sbc_check_prot(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb,
706 u32 sectors, bool is_write)
708 u8 protect = cdb[1] >> 5;
709 int sp_ops = cmd->se_sess->sup_prot_ops;
710 int pi_prot_type = dev->dev_attrib.pi_prot_type;
711 bool fabric_prot = false;
713 if (!cmd->t_prot_sg || !cmd->t_prot_nents) {
714 if (unlikely(protect &&
715 !dev->dev_attrib.pi_prot_type && !cmd->se_sess->sess_prot_type)) {
716 pr_err("CDB contains protect bit, but device + fabric does"
717 " not advertise PROTECT=1 feature bit\n");
718 return TCM_INVALID_CDB_FIELD;
720 if (cmd->prot_pto)
721 return TCM_NO_SENSE;
724 switch (dev->dev_attrib.pi_prot_type) {
725 case TARGET_DIF_TYPE3_PROT:
726 cmd->reftag_seed = 0xffffffff;
727 break;
728 case TARGET_DIF_TYPE2_PROT:
729 if (protect)
730 return TCM_INVALID_CDB_FIELD;
732 cmd->reftag_seed = cmd->t_task_lba;
733 break;
734 case TARGET_DIF_TYPE1_PROT:
735 cmd->reftag_seed = cmd->t_task_lba;
736 break;
737 case TARGET_DIF_TYPE0_PROT:
739 * See if the fabric supports T10-PI, and the session has been
740 * configured to allow export PROTECT=1 feature bit with backend
741 * devices that don't support T10-PI.
743 fabric_prot = is_write ?
744 !!(sp_ops & (TARGET_PROT_DOUT_PASS | TARGET_PROT_DOUT_STRIP)) :
745 !!(sp_ops & (TARGET_PROT_DIN_PASS | TARGET_PROT_DIN_INSERT));
747 if (fabric_prot && cmd->se_sess->sess_prot_type) {
748 pi_prot_type = cmd->se_sess->sess_prot_type;
749 break;
751 if (!protect)
752 return TCM_NO_SENSE;
753 /* Fallthrough */
754 default:
755 pr_err("Unable to determine pi_prot_type for CDB: 0x%02x "
756 "PROTECT: 0x%02x\n", cdb[0], protect);
757 return TCM_INVALID_CDB_FIELD;
760 if (sbc_set_prot_op_checks(protect, fabric_prot, pi_prot_type, is_write, cmd))
761 return TCM_INVALID_CDB_FIELD;
763 cmd->prot_type = pi_prot_type;
764 cmd->prot_length = dev->prot_length * sectors;
767 * In case protection information exists over the wire
768 * we modify command data length to describe pure data.
769 * The actual transfer length is data length + protection
770 * length
772 if (protect)
773 cmd->data_length = sectors * dev->dev_attrib.block_size;
775 pr_debug("%s: prot_type=%d, data_length=%d, prot_length=%d "
776 "prot_op=%d prot_checks=%d\n",
777 __func__, cmd->prot_type, cmd->data_length, cmd->prot_length,
778 cmd->prot_op, cmd->prot_checks);
780 return TCM_NO_SENSE;
783 static int
784 sbc_check_dpofua(struct se_device *dev, struct se_cmd *cmd, unsigned char *cdb)
786 if (cdb[1] & 0x10) {
787 /* see explanation in spc_emulate_modesense */
788 if (!target_check_fua(dev)) {
789 pr_err("Got CDB: 0x%02x with DPO bit set, but device"
790 " does not advertise support for DPO\n", cdb[0]);
791 return -EINVAL;
794 if (cdb[1] & 0x8) {
795 if (!target_check_fua(dev)) {
796 pr_err("Got CDB: 0x%02x with FUA bit set, but device"
797 " does not advertise support for FUA write\n",
798 cdb[0]);
799 return -EINVAL;
801 cmd->se_cmd_flags |= SCF_FUA;
803 return 0;
806 sense_reason_t
807 sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
809 struct se_device *dev = cmd->se_dev;
810 unsigned char *cdb = cmd->t_task_cdb;
811 unsigned int size;
812 u32 sectors = 0;
813 sense_reason_t ret;
815 cmd->protocol_data = ops;
817 switch (cdb[0]) {
818 case READ_6:
819 sectors = transport_get_sectors_6(cdb);
820 cmd->t_task_lba = transport_lba_21(cdb);
821 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
822 cmd->execute_cmd = sbc_execute_rw;
823 break;
824 case READ_10:
825 sectors = transport_get_sectors_10(cdb);
826 cmd->t_task_lba = transport_lba_32(cdb);
828 if (sbc_check_dpofua(dev, cmd, cdb))
829 return TCM_INVALID_CDB_FIELD;
831 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
832 if (ret)
833 return ret;
835 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
836 cmd->execute_cmd = sbc_execute_rw;
837 break;
838 case READ_12:
839 sectors = transport_get_sectors_12(cdb);
840 cmd->t_task_lba = transport_lba_32(cdb);
842 if (sbc_check_dpofua(dev, cmd, cdb))
843 return TCM_INVALID_CDB_FIELD;
845 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
846 if (ret)
847 return ret;
849 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
850 cmd->execute_cmd = sbc_execute_rw;
851 break;
852 case READ_16:
853 sectors = transport_get_sectors_16(cdb);
854 cmd->t_task_lba = transport_lba_64(cdb);
856 if (sbc_check_dpofua(dev, cmd, cdb))
857 return TCM_INVALID_CDB_FIELD;
859 ret = sbc_check_prot(dev, cmd, cdb, sectors, false);
860 if (ret)
861 return ret;
863 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
864 cmd->execute_cmd = sbc_execute_rw;
865 break;
866 case WRITE_6:
867 sectors = transport_get_sectors_6(cdb);
868 cmd->t_task_lba = transport_lba_21(cdb);
869 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
870 cmd->execute_cmd = sbc_execute_rw;
871 break;
872 case WRITE_10:
873 case WRITE_VERIFY:
874 sectors = transport_get_sectors_10(cdb);
875 cmd->t_task_lba = transport_lba_32(cdb);
877 if (sbc_check_dpofua(dev, cmd, cdb))
878 return TCM_INVALID_CDB_FIELD;
880 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
881 if (ret)
882 return ret;
884 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
885 cmd->execute_cmd = sbc_execute_rw;
886 break;
887 case WRITE_12:
888 sectors = transport_get_sectors_12(cdb);
889 cmd->t_task_lba = transport_lba_32(cdb);
891 if (sbc_check_dpofua(dev, cmd, cdb))
892 return TCM_INVALID_CDB_FIELD;
894 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
895 if (ret)
896 return ret;
898 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
899 cmd->execute_cmd = sbc_execute_rw;
900 break;
901 case WRITE_16:
902 case WRITE_VERIFY_16:
903 sectors = transport_get_sectors_16(cdb);
904 cmd->t_task_lba = transport_lba_64(cdb);
906 if (sbc_check_dpofua(dev, cmd, cdb))
907 return TCM_INVALID_CDB_FIELD;
909 ret = sbc_check_prot(dev, cmd, cdb, sectors, true);
910 if (ret)
911 return ret;
913 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
914 cmd->execute_cmd = sbc_execute_rw;
915 break;
916 case XDWRITEREAD_10:
917 if (cmd->data_direction != DMA_TO_DEVICE ||
918 !(cmd->se_cmd_flags & SCF_BIDI))
919 return TCM_INVALID_CDB_FIELD;
920 sectors = transport_get_sectors_10(cdb);
922 if (sbc_check_dpofua(dev, cmd, cdb))
923 return TCM_INVALID_CDB_FIELD;
925 cmd->t_task_lba = transport_lba_32(cdb);
926 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
929 * Setup BIDI XOR callback to be run after I/O completion.
931 cmd->execute_cmd = sbc_execute_rw;
932 cmd->transport_complete_callback = &xdreadwrite_callback;
933 break;
934 case VARIABLE_LENGTH_CMD:
936 u16 service_action = get_unaligned_be16(&cdb[8]);
937 switch (service_action) {
938 case XDWRITEREAD_32:
939 sectors = transport_get_sectors_32(cdb);
941 if (sbc_check_dpofua(dev, cmd, cdb))
942 return TCM_INVALID_CDB_FIELD;
944 * Use WRITE_32 and READ_32 opcodes for the emulated
945 * XDWRITE_READ_32 logic.
947 cmd->t_task_lba = transport_lba_64_ext(cdb);
948 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB;
951 * Setup BIDI XOR callback to be run during after I/O
952 * completion.
954 cmd->execute_cmd = sbc_execute_rw;
955 cmd->transport_complete_callback = &xdreadwrite_callback;
956 break;
957 case WRITE_SAME_32:
958 sectors = transport_get_sectors_32(cdb);
959 if (!sectors) {
960 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
961 " supported\n");
962 return TCM_INVALID_CDB_FIELD;
965 size = sbc_get_size(cmd, 1);
966 cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
968 ret = sbc_setup_write_same(cmd, &cdb[10], ops);
969 if (ret)
970 return ret;
971 break;
972 default:
973 pr_err("VARIABLE_LENGTH_CMD service action"
974 " 0x%04x not supported\n", service_action);
975 return TCM_UNSUPPORTED_SCSI_OPCODE;
977 break;
979 case COMPARE_AND_WRITE:
980 if (!dev->dev_attrib.emulate_caw) {
981 pr_err_ratelimited("se_device %s/%s (vpd_unit_serial %s) reject"
982 " COMPARE_AND_WRITE\n", dev->se_hba->backend->ops->name,
983 dev->dev_group.cg_item.ci_name, dev->t10_wwn.unit_serial);
984 return TCM_UNSUPPORTED_SCSI_OPCODE;
986 sectors = cdb[13];
988 * Currently enforce COMPARE_AND_WRITE for a single sector
990 if (sectors > 1) {
991 pr_err("COMPARE_AND_WRITE contains NoLB: %u greater"
992 " than 1\n", sectors);
993 return TCM_INVALID_CDB_FIELD;
995 if (sbc_check_dpofua(dev, cmd, cdb))
996 return TCM_INVALID_CDB_FIELD;
999 * Double size because we have two buffers, note that
1000 * zero is not an error..
1002 size = 2 * sbc_get_size(cmd, sectors);
1003 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1004 cmd->t_task_nolb = sectors;
1005 cmd->se_cmd_flags |= SCF_SCSI_DATA_CDB | SCF_COMPARE_AND_WRITE;
1006 cmd->execute_cmd = sbc_compare_and_write;
1007 cmd->transport_complete_callback = compare_and_write_callback;
1008 break;
1009 case READ_CAPACITY:
1010 size = READ_CAP_LEN;
1011 cmd->execute_cmd = sbc_emulate_readcapacity;
1012 break;
1013 case SERVICE_ACTION_IN_16:
1014 switch (cmd->t_task_cdb[1] & 0x1f) {
1015 case SAI_READ_CAPACITY_16:
1016 cmd->execute_cmd = sbc_emulate_readcapacity_16;
1017 break;
1018 case SAI_REPORT_REFERRALS:
1019 cmd->execute_cmd = target_emulate_report_referrals;
1020 break;
1021 default:
1022 pr_err("Unsupported SA: 0x%02x\n",
1023 cmd->t_task_cdb[1] & 0x1f);
1024 return TCM_INVALID_CDB_FIELD;
1026 size = get_unaligned_be32(&cdb[10]);
1027 break;
1028 case SYNCHRONIZE_CACHE:
1029 case SYNCHRONIZE_CACHE_16:
1030 if (cdb[0] == SYNCHRONIZE_CACHE) {
1031 sectors = transport_get_sectors_10(cdb);
1032 cmd->t_task_lba = transport_lba_32(cdb);
1033 } else {
1034 sectors = transport_get_sectors_16(cdb);
1035 cmd->t_task_lba = transport_lba_64(cdb);
1037 if (ops->execute_sync_cache) {
1038 cmd->execute_cmd = ops->execute_sync_cache;
1039 goto check_lba;
1041 size = 0;
1042 cmd->execute_cmd = sbc_emulate_noop;
1043 break;
1044 case UNMAP:
1045 if (!ops->execute_unmap)
1046 return TCM_UNSUPPORTED_SCSI_OPCODE;
1048 if (!dev->dev_attrib.emulate_tpu) {
1049 pr_err("Got UNMAP, but backend device has"
1050 " emulate_tpu disabled\n");
1051 return TCM_UNSUPPORTED_SCSI_OPCODE;
1053 size = get_unaligned_be16(&cdb[7]);
1054 cmd->execute_cmd = sbc_execute_unmap;
1055 break;
1056 case WRITE_SAME_16:
1057 sectors = transport_get_sectors_16(cdb);
1058 if (!sectors) {
1059 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1060 return TCM_INVALID_CDB_FIELD;
1063 size = sbc_get_size(cmd, 1);
1064 cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
1066 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1067 if (ret)
1068 return ret;
1069 break;
1070 case WRITE_SAME:
1071 sectors = transport_get_sectors_10(cdb);
1072 if (!sectors) {
1073 pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
1074 return TCM_INVALID_CDB_FIELD;
1077 size = sbc_get_size(cmd, 1);
1078 cmd->t_task_lba = get_unaligned_be32(&cdb[2]);
1081 * Follow sbcr26 with WRITE_SAME (10) and check for the existence
1082 * of byte 1 bit 3 UNMAP instead of original reserved field
1084 ret = sbc_setup_write_same(cmd, &cdb[1], ops);
1085 if (ret)
1086 return ret;
1087 break;
1088 case VERIFY:
1089 case VERIFY_16:
1090 size = 0;
1091 if (cdb[0] == VERIFY) {
1092 sectors = transport_get_sectors_10(cdb);
1093 cmd->t_task_lba = transport_lba_32(cdb);
1094 } else {
1095 sectors = transport_get_sectors_16(cdb);
1096 cmd->t_task_lba = transport_lba_64(cdb);
1098 cmd->execute_cmd = sbc_emulate_noop;
1099 goto check_lba;
1100 case REZERO_UNIT:
1101 case SEEK_6:
1102 case SEEK_10:
1104 * There are still clients out there which use these old SCSI-2
1105 * commands. This mainly happens when running VMs with legacy
1106 * guest systems, connected via SCSI command pass-through to
1107 * iSCSI targets. Make them happy and return status GOOD.
1109 size = 0;
1110 cmd->execute_cmd = sbc_emulate_noop;
1111 break;
1112 case START_STOP:
1113 size = 0;
1114 cmd->execute_cmd = sbc_emulate_startstop;
1115 break;
1116 default:
1117 ret = spc_parse_cdb(cmd, &size);
1118 if (ret)
1119 return ret;
1122 /* reject any command that we don't have a handler for */
1123 if (!cmd->execute_cmd)
1124 return TCM_UNSUPPORTED_SCSI_OPCODE;
1126 if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
1127 unsigned long long end_lba;
1128 check_lba:
1129 end_lba = dev->transport->get_blocks(dev) + 1;
1130 if (((cmd->t_task_lba + sectors) < cmd->t_task_lba) ||
1131 ((cmd->t_task_lba + sectors) > end_lba)) {
1132 pr_err("cmd exceeds last lba %llu "
1133 "(lba %llu, sectors %u)\n",
1134 end_lba, cmd->t_task_lba, sectors);
1135 return TCM_ADDRESS_OUT_OF_RANGE;
1138 if (!(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE))
1139 size = sbc_get_size(cmd, sectors);
1142 return target_cmd_size_check(cmd, size);
1144 EXPORT_SYMBOL(sbc_parse_cdb);
1146 u32 sbc_get_device_type(struct se_device *dev)
1148 return TYPE_DISK;
1150 EXPORT_SYMBOL(sbc_get_device_type);
1152 static sense_reason_t
1153 sbc_execute_unmap(struct se_cmd *cmd)
1155 struct sbc_ops *ops = cmd->protocol_data;
1156 struct se_device *dev = cmd->se_dev;
1157 unsigned char *buf, *ptr = NULL;
1158 sector_t lba;
1159 int size;
1160 u32 range;
1161 sense_reason_t ret = 0;
1162 int dl, bd_dl;
1164 /* We never set ANC_SUP */
1165 if (cmd->t_task_cdb[1])
1166 return TCM_INVALID_CDB_FIELD;
1168 if (cmd->data_length == 0) {
1169 target_complete_cmd(cmd, SAM_STAT_GOOD);
1170 return 0;
1173 if (cmd->data_length < 8) {
1174 pr_warn("UNMAP parameter list length %u too small\n",
1175 cmd->data_length);
1176 return TCM_PARAMETER_LIST_LENGTH_ERROR;
1179 buf = transport_kmap_data_sg(cmd);
1180 if (!buf)
1181 return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
1183 dl = get_unaligned_be16(&buf[0]);
1184 bd_dl = get_unaligned_be16(&buf[2]);
1186 size = cmd->data_length - 8;
1187 if (bd_dl > size)
1188 pr_warn("UNMAP parameter list length %u too small, ignoring bd_dl %u\n",
1189 cmd->data_length, bd_dl);
1190 else
1191 size = bd_dl;
1193 if (size / 16 > dev->dev_attrib.max_unmap_block_desc_count) {
1194 ret = TCM_INVALID_PARAMETER_LIST;
1195 goto err;
1198 /* First UNMAP block descriptor starts at 8 byte offset */
1199 ptr = &buf[8];
1200 pr_debug("UNMAP: Sub: %s Using dl: %u bd_dl: %u size: %u"
1201 " ptr: %p\n", dev->transport->name, dl, bd_dl, size, ptr);
1203 while (size >= 16) {
1204 lba = get_unaligned_be64(&ptr[0]);
1205 range = get_unaligned_be32(&ptr[8]);
1206 pr_debug("UNMAP: Using lba: %llu and range: %u\n",
1207 (unsigned long long)lba, range);
1209 if (range > dev->dev_attrib.max_unmap_lba_count) {
1210 ret = TCM_INVALID_PARAMETER_LIST;
1211 goto err;
1214 if (lba + range > dev->transport->get_blocks(dev) + 1) {
1215 ret = TCM_ADDRESS_OUT_OF_RANGE;
1216 goto err;
1219 if (range) {
1220 ret = ops->execute_unmap(cmd, lba, range);
1221 if (ret)
1222 goto err;
1225 ptr += 16;
1226 size -= 16;
1229 err:
1230 transport_kunmap_data_sg(cmd);
1231 if (!ret)
1232 target_complete_cmd(cmd, GOOD);
1233 return ret;
1236 void
1237 sbc_dif_generate(struct se_cmd *cmd)
1239 struct se_device *dev = cmd->se_dev;
1240 struct t10_pi_tuple *sdt;
1241 struct scatterlist *dsg = cmd->t_data_sg, *psg;
1242 sector_t sector = cmd->t_task_lba;
1243 void *daddr, *paddr;
1244 int i, j, offset = 0;
1245 unsigned int block_size = dev->dev_attrib.block_size;
1247 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1248 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1249 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1251 for (j = 0; j < psg->length;
1252 j += sizeof(*sdt)) {
1253 __u16 crc;
1254 unsigned int avail;
1256 if (offset >= dsg->length) {
1257 offset -= dsg->length;
1258 kunmap_atomic(daddr - dsg->offset);
1259 dsg = sg_next(dsg);
1260 if (!dsg) {
1261 kunmap_atomic(paddr - psg->offset);
1262 return;
1264 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1267 sdt = paddr + j;
1268 avail = min(block_size, dsg->length - offset);
1269 crc = crc_t10dif(daddr + offset, avail);
1270 if (avail < block_size) {
1271 kunmap_atomic(daddr - dsg->offset);
1272 dsg = sg_next(dsg);
1273 if (!dsg) {
1274 kunmap_atomic(paddr - psg->offset);
1275 return;
1277 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1278 offset = block_size - avail;
1279 crc = crc_t10dif_update(crc, daddr, offset);
1280 } else {
1281 offset += block_size;
1284 sdt->guard_tag = cpu_to_be16(crc);
1285 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT)
1286 sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
1287 sdt->app_tag = 0;
1289 pr_debug("DIF %s INSERT sector: %llu guard_tag: 0x%04x"
1290 " app_tag: 0x%04x ref_tag: %u\n",
1291 (cmd->data_direction == DMA_TO_DEVICE) ?
1292 "WRITE" : "READ", (unsigned long long)sector,
1293 sdt->guard_tag, sdt->app_tag,
1294 be32_to_cpu(sdt->ref_tag));
1296 sector++;
1299 kunmap_atomic(daddr - dsg->offset);
1300 kunmap_atomic(paddr - psg->offset);
1304 static sense_reason_t
1305 sbc_dif_v1_verify(struct se_cmd *cmd, struct t10_pi_tuple *sdt,
1306 __u16 crc, sector_t sector, unsigned int ei_lba)
1308 __be16 csum;
1310 if (!(cmd->prot_checks & TARGET_DIF_CHECK_GUARD))
1311 goto check_ref;
1313 csum = cpu_to_be16(crc);
1315 if (sdt->guard_tag != csum) {
1316 pr_err("DIFv1 checksum failed on sector %llu guard tag 0x%04x"
1317 " csum 0x%04x\n", (unsigned long long)sector,
1318 be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
1319 return TCM_LOGICAL_BLOCK_GUARD_CHECK_FAILED;
1322 check_ref:
1323 if (!(cmd->prot_checks & TARGET_DIF_CHECK_REFTAG))
1324 return 0;
1326 if (cmd->prot_type == TARGET_DIF_TYPE1_PROT &&
1327 be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
1328 pr_err("DIFv1 Type 1 reference failed on sector: %llu tag: 0x%08x"
1329 " sector MSB: 0x%08x\n", (unsigned long long)sector,
1330 be32_to_cpu(sdt->ref_tag), (u32)(sector & 0xffffffff));
1331 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1334 if (cmd->prot_type == TARGET_DIF_TYPE2_PROT &&
1335 be32_to_cpu(sdt->ref_tag) != ei_lba) {
1336 pr_err("DIFv1 Type 2 reference failed on sector: %llu tag: 0x%08x"
1337 " ei_lba: 0x%08x\n", (unsigned long long)sector,
1338 be32_to_cpu(sdt->ref_tag), ei_lba);
1339 return TCM_LOGICAL_BLOCK_REF_TAG_CHECK_FAILED;
1342 return 0;
1345 void sbc_dif_copy_prot(struct se_cmd *cmd, unsigned int sectors, bool read,
1346 struct scatterlist *sg, int sg_off)
1348 struct se_device *dev = cmd->se_dev;
1349 struct scatterlist *psg;
1350 void *paddr, *addr;
1351 unsigned int i, len, left;
1352 unsigned int offset = sg_off;
1354 if (!sg)
1355 return;
1357 left = sectors * dev->prot_length;
1359 for_each_sg(cmd->t_prot_sg, psg, cmd->t_prot_nents, i) {
1360 unsigned int psg_len, copied = 0;
1362 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1363 psg_len = min(left, psg->length);
1364 while (psg_len) {
1365 len = min(psg_len, sg->length - offset);
1366 addr = kmap_atomic(sg_page(sg)) + sg->offset + offset;
1368 if (read)
1369 memcpy(paddr + copied, addr, len);
1370 else
1371 memcpy(addr, paddr + copied, len);
1373 left -= len;
1374 offset += len;
1375 copied += len;
1376 psg_len -= len;
1378 kunmap_atomic(addr - sg->offset - offset);
1380 if (offset >= sg->length) {
1381 sg = sg_next(sg);
1382 offset = 0;
1385 kunmap_atomic(paddr - psg->offset);
1388 EXPORT_SYMBOL(sbc_dif_copy_prot);
1390 sense_reason_t
1391 sbc_dif_verify(struct se_cmd *cmd, sector_t start, unsigned int sectors,
1392 unsigned int ei_lba, struct scatterlist *psg, int psg_off)
1394 struct se_device *dev = cmd->se_dev;
1395 struct t10_pi_tuple *sdt;
1396 struct scatterlist *dsg = cmd->t_data_sg;
1397 sector_t sector = start;
1398 void *daddr, *paddr;
1399 int i;
1400 sense_reason_t rc;
1401 int dsg_off = 0;
1402 unsigned int block_size = dev->dev_attrib.block_size;
1404 for (; psg && sector < start + sectors; psg = sg_next(psg)) {
1405 paddr = kmap_atomic(sg_page(psg)) + psg->offset;
1406 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1408 for (i = psg_off; i < psg->length &&
1409 sector < start + sectors;
1410 i += sizeof(*sdt)) {
1411 __u16 crc;
1412 unsigned int avail;
1414 if (dsg_off >= dsg->length) {
1415 dsg_off -= dsg->length;
1416 kunmap_atomic(daddr - dsg->offset);
1417 dsg = sg_next(dsg);
1418 if (!dsg) {
1419 kunmap_atomic(paddr - psg->offset);
1420 return 0;
1422 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1425 sdt = paddr + i;
1427 pr_debug("DIF READ sector: %llu guard_tag: 0x%04x"
1428 " app_tag: 0x%04x ref_tag: %u\n",
1429 (unsigned long long)sector, sdt->guard_tag,
1430 sdt->app_tag, be32_to_cpu(sdt->ref_tag));
1432 if (sdt->app_tag == T10_PI_APP_ESCAPE) {
1433 dsg_off += block_size;
1434 goto next;
1437 avail = min(block_size, dsg->length - dsg_off);
1438 crc = crc_t10dif(daddr + dsg_off, avail);
1439 if (avail < block_size) {
1440 kunmap_atomic(daddr - dsg->offset);
1441 dsg = sg_next(dsg);
1442 if (!dsg) {
1443 kunmap_atomic(paddr - psg->offset);
1444 return 0;
1446 daddr = kmap_atomic(sg_page(dsg)) + dsg->offset;
1447 dsg_off = block_size - avail;
1448 crc = crc_t10dif_update(crc, daddr, dsg_off);
1449 } else {
1450 dsg_off += block_size;
1453 rc = sbc_dif_v1_verify(cmd, sdt, crc, sector, ei_lba);
1454 if (rc) {
1455 kunmap_atomic(daddr - dsg->offset);
1456 kunmap_atomic(paddr - psg->offset);
1457 cmd->bad_sector = sector;
1458 return rc;
1460 next:
1461 sector++;
1462 ei_lba++;
1465 psg_off = 0;
1466 kunmap_atomic(daddr - dsg->offset);
1467 kunmap_atomic(paddr - psg->offset);
1470 return 0;
1472 EXPORT_SYMBOL(sbc_dif_verify);